When the pressure cylinder of an extrusion press is filled with an explosive mass, for example a mass intended for propellant charges or when propellant material is placed in the pressure cylinder in the form of rolled sheets, it is often impossible to prevent air or other gases from being included in the pressure cylinder. If the pressure in the pressure cylinder is increased too rapidly, i.e., if the compression is increased at too high a rate, either during the precompression process or during the extrusion process, the enclosed gas is compressed nearly adiabatically. During the adiabatic compression, the gas may reach the ignition temperature of the surrounding compressed explosive mass, resulting in burning or explosion.